Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
Mathematics
Mathematics
Problem
Explain why
d
d
x
sec
x
\dfrac{d}{dx}\sec x
d
x
d
sec
x
is positive for
0
<
x
<
π
2
0<x<\dfrac{\pi}{2}
0
<
x
<
2
π
.
Browse the problem library